x86, kaslr: boot-time selectable with hibernation
Changes kASLR from being compile-time selectable (blocked by
CONFIG_HIBERNATION), to being boot-time selectable (with hibernation
available by default) via the "kaslr" kernel command line.
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/arch/x86/boot/compressed/aslr.c b/arch/x86/boot/compressed/aslr.c
index 4dbf967..fc6091a 100644
--- a/arch/x86/boot/compressed/aslr.c
+++ b/arch/x86/boot/compressed/aslr.c
@@ -289,10 +289,17 @@
unsigned long choice = (unsigned long)output;
unsigned long random;
- if (cmdline_find_option_bool("nokaslr")) {
- debug_putstr("KASLR disabled...\n");
+#ifdef CONFIG_HIBERNATION
+ if (!cmdline_find_option_bool("kaslr")) {
+ debug_putstr("KASLR disabled by default...\n");
goto out;
}
+#else
+ if (cmdline_find_option_bool("nokaslr")) {
+ debug_putstr("KASLR disabled by cmdline...\n");
+ goto out;
+ }
+#endif
/* Record the various known unsafe memory ranges. */
mem_avoid_init((unsigned long)input, input_size,